A view from the top

In Django, a view is defined as a callable that accepts a request and returns a response. It is usually a function or a class with a special class method such as as_view().

In both cases, we create a normal Python function that takes an HTTPRequest as the first argument and returns an HTTPResponse. A URLConf can also pass additional arguments to this function. These arguments can be captured from parts of the URL or set to default values.

Here is what a simple view looks like:

# In views.py
from django.http import HttpResponse

def hello_fn(request, name="World"):
    return HttpResponse("Hello {}!".format(name))

Our two-line view function is quite simple to understand. We are currently not doing anything with the request argument. We can examine a request to better understand the context in which the view was called, for example by looking at the GET/POST parameters, URI path, or HTTP headers such as REMOTE_ADDR.

Its corresponding lines in URLConf would be as follows:

# In...